Technical Field
This invention generally relates to novel insecticidal compositions and methods for use of the same for controlling a target pest.
Description of the Related Art
General household insect pests have the potential to cause nuisance or harm to person and property. Nuisance insects can infest an individual's living environment at any place and at any time. Infestations can cause anxiety, physical ailments, and economic hardship. Although bed bugs have not been proven to transmit diseases, they are classified as a major public health problem due to their negative impact on the quality of life. Bed bugs cause a number of adverse health effects, including skin rashes, blisters, severe itching, loss of sleep, psychological effects, and allergic symptoms. Bed bug infestations can also create economic hardship, such as high treatment costs, displacement, decreased work productivity, and loss of wages. In commercial setting, such as in hotels, theaters, and residential complexes, revenue can be significantly impacted by infestations due to treatment costs and loss of services.
Various insecticide compositions have been developed to control bed bugs and other household pests. The primary objective in developing an insecticidal compound is its “knockdown” and “mortality” potential. Knockdown refers to quick, short-term, immobilization. Knockdown usually occurs within a short period of time, but is dependent on the pest. Pests can recover from knockdown immobilization depending on their tolerance for the insecticides and their recovery abilities. Mortality refers to the death of the pest.
An optimal insecticide composition would have a knockdown and mortality rate near 100% and its application method would be proficient at reaching its intended target. Over the years, widespread use of synthetic chemical insecticides has led to insecticide resistance among certain household insects. Insecticides, such as pyrethroids, carbamates, and organophosphates are not as effective as they were 15 years ago. Insecticide resistance has been postulated to be the key initiator of the resurgence in bed bugs. Contact insecticides with no residual effects, such as pyrethrum, are ineffective even when encountering a non-resistant strain if the application method fails to reach its target. Other, insecticides, such as chlorfenapyr alone, provide residual effects achieving a reduction in the pest populations only after several weeks. An insecticide composition with no known insect resistance that can be effectively delivered to acquire a knockdown and mortality rate near 100% is desirable to ensure effective protection of persons and property against general household pests.
Synergists are compounds that are non-toxic or negligibly toxic to a pest at a set dosage but are able to enhance the toxicity of the active chemical with which they are combined. Piperonyl butoxide (PBO) and N-Octyl bicycloheptene dicarboximide (MGK-264) are common insecticide synergists in commercial formulations. Although previously believed to be fairly non-toxic to mammals, indoor PBO use is being scrutinized by regulatory agencies and other groups for potential detrimental effects to humans and animals. MGK-264 is not as effective as PBO and is slightly more toxic.
The use of plant essential oils as insecticides has been reported, as described in U.S. Pat. Nos. 4,518,593, 7,534,447 and 6,231,865, and in U.S. Pub. No. 2013/0142893 (the full disclosures of which are incorporated herein by reference in their entireties). However, most natural products do not provide adequate control of pests particularly during large infestations. Consequently, there is a need in the art for novel synergistic and residual insecticidal compositions that addresses these concerns. The present invention provides these and relates advantages.